Iâ€™ve searched and canâ€™t find the answer; whatâ€™s the thread size for the oil drain line going into the fitting on the engine block? Iâ€™m installing an aftermarket turbo with a custom drain line. My plan is to run a line off the turbo into a new hose connection that fits into the stock fitting but I donâ€™t know the stock thread size. Thanks!

I know the threads on the block itself are 3/4 NPT. i want to say they fitting is 1/2 but i cant remember. when i upgraded my line i just used a -12an to 3/4NPT Connector on the end of my hose, and got rid of the fitting. you can also replace the fitting with a 3/4 to whatever size line you want to run. see the link below.

MortifydPenguin Wrote:I know the threads on the block itself are 3/4 NPT. i want to say they fitting is 1/2 but i cant remember. when i upgraded my line i just used a -12an to 3/4NPT Connector on the end of my hose, and got rid of the fitting. you can also replace the fitting with a 3/4 to whatever size line you want to run. see the link below.